<html>
    <head>
        <title>欢迎您！</title>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    </head>
    <body>
        <form action="welcome" method="get">
            请输入用户名：<input type="text" name="username"><br>
            <input type="submit" value="提交">
        </form>
    </body>
</html>